jmu-Java-03面向對象-06-繼承覆蓋綜合練習-Person、Student、Employee、Company (20 分) ///答案，不包括解析

 

定義Person抽象類，Student類、Company類，Employee類。

Person類的屬性：String name, int age, boolean gender
Person類的方法:

public Person(String name, int age, boolean gender);
public String toString();         //返回"name-age-gender"格式的字符串
public boolean equals(Object obj);//比較name、age、gender,都相同返回true,否則返回false

Student類繼承自Person，屬性:String stuNo, String clazz
Student類的方法:

//建議使用super復用Person類的相關有參構造函數
public Student(String name, int age, boolean gender, String stuNo, String clazz);
public String toString();         //返回 “Student:person的toString-stuNo-clazz”格式的字符串
public boolean equals(Object obj);//首先調用父類的equals方法,如果返回true，則繼續比較stuNo與clazz。

Company類屬性：String name
Company類方法:

public Company(String name);
public String toString();         //直接返回name
public boolean equals(Object obj);//name相同返回true

Employee類繼承自Person，屬性：Company company, double salary
Employee類方法：

//建議使用super復用Person類的相關有參構造函數
public Employee(String name, int age, boolean gender, double salary, Company company);
public String toString();         //返回"Employee:person的toString-company-salary"格式的字符串
public boolean equals(Object obj);//首先調用父類的equals方法,如果返回true。再比較company與salary。
//比較salary屬性時，使用DecimalFormat df = new DecimalFormat("#.#");保留1位小數

編寫equals方法重要說明：

1. 對Employee的company屬性的比較。要考慮傳入為null的情況。如果company不為null且傳入為null，返回false
2. 對所有String字符類型比較時，也要考慮null情況。

提示

1. 排序可使用Collections.sort
2. equals方法要考慮周全

main方法說明

1. 創建若干Student對象、Employee對象。
   輸入s，然后依次輸入name age gender stuNo clazz創建Student對象。
   輸入e，然后依次輸入name age gender salary company創建Employee對象。
   然后將創建好的對象放入List<Person> personList。輸入其他字符，則結束創建。
   創建說明:對於String類型，如果為null則不創建對象，而賦值為null。對於company屬性，如果為null則賦值為null，否則創建相應的Company對象。

2. 對personList中的元素實現先按照姓名升序排序，姓名相同再按照年齡升序排序。提示：可使用Comparable<Person>或Comparator<Person>

3. 接受輸入，如果輸入為exit則return退出程序，否則繼續下面步驟。

4. 將personList中的元素按照類型分別放到stuList與empList。注意：不要將兩個內容相同的對象放入列表（是否相同是根據equals返回結果進行判定）。

5. 輸出字符串stuList，然后輸出stuList中的每個對象。

6. 輸出字符串empList，然后輸出empList中的每個對象。

1-3為一個測試點 4-6為一個測試點

輸入樣例：

s zhang 23 false 001 net15
e wang 18 true 3000.51 IBM
s zhang 23 false 001 net15
e bo 25 true 5000.51 IBM
e bo 25 true 5000.52 IBM
e bo 18 true 5000.54 IBM
e tan 25 true 5000.56 IBM
e tan 25 true 5000.51 IBM
s wang 17 false 002 null
s wang 17 false 002 null
e hua 16 false 1000 null
s wang 17 false 002 net16
e hua 16 false 1000 null
e hua 18 false 1234 MicroSoft
!
continue

輸出樣例：

Employee:bo-18-true-IBM-5000.54
Employee:bo-25-true-IBM-5000.51
Employee:bo-25-true-IBM-5000.52
Employee:hua-16-false-null-1000.0
Employee:hua-16-false-null-1000.0
Employee:hua-18-false-MicroSoft-1234.0
Employee:tan-25-true-IBM-5000.56
Employee:tan-25-true-IBM-5000.51
Student:wang-17-false-002-null
Student:wang-17-false-002-null
Student:wang-17-false-002-net16
Employee:wang-18-true-IBM-3000.51
Student:zhang-23-false-001-net15
Student:zhang-23-false-001-net15
stuList
Student:wang-17-false-002-null
Student:wang-17-false-002-net16
Student:zhang-23-false-001-net15
empList
Employee:bo-18-true-IBM-5000.54
Employee:bo-25-true-IBM-5000.51
Employee:hua-16-false-null-1000.0
Employee:hua-18-false-MicroSoft-1234.0
Employee:tan-25-true-IBM-5000.56
Employee:tan-25-true-IBM-5000.51
Employee:wang-18-true-IBM-3000.51
答案

import java.awt.List;
import java.awt.TexturePaint;
import java.lang.reflect.Array;
import java.text.DecimalFormat;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.Comparator;
import java.util.Scanner;

import javax.naming.BinaryRefAddr;
import javax.security.auth.SubjectDomainCombiner;
import javax.sound.sampled.Line;

class Person{
	private String name;
	private int avg;
	private boolean gender;
	private String str;
	public Person(String name, int avg, boolean gender,String str) {
		this.name = name;
		this.avg = avg;
		this.gender = gender;
		this.str = str;
	}
	public String toString() {
		return name+"-"+avg+"-"+gender;
	}
	public boolean equals(Object obj) {
		Person aPerson = (Person)obj;
		if(aPerson.name==null||this.name==null) {
			return false;
		}
		if(aPerson.name.compareTo(this.name)==0&&aPerson.avg==this.avg&&aPerson.gender==this.gender) {
			return true;
		}
		return false;
	}
	public String getName() {
		return name;
	}
	public int getAvg() {
		return avg;
	}
	public String getStr() {
		return str;
	}
	public boolean getGender() {
		return gender;
	}
}

class Student extends Person {
	private String stuNo;
	private String clazz;
	
	public Student(String name, int avg, boolean gender, String str, String stuNo, String clazz) {
		super(name, avg, gender, str);
		this.stuNo = stuNo;
		this.clazz = clazz;
	}
	public String toString() {
		return super.toString()+"-"+stuNo+"-"+clazz;
	}
	public boolean equals(Object obj) {
		Student a = (Student)obj;
		if(super.equals(obj)==true) {
			if(this.stuNo==null|this.clazz==null||a.clazz==null||a.stuNo==null) {
				return false;
			}
			if(this.clazz.compareTo(a.clazz)==0&&this.stuNo.compareTo(a.stuNo)==0)
				return true;
		}
		return false;
	}
	public String getStuNo() {
		return stuNo;
	}
	public String getClazz() {
		return clazz;
	}
}

class Company{
	private String name;
	public Company(String name) {
		this.name = name;
	}
	@Override
	public String toString() {
		return name;
	}
	@Override
	public boolean equals(Object obj) {
		if (this == obj)
			return true;
		if (obj == null)
			return false;
		if (getClass() != obj.getClass())
			return false;
		Company other = (Company) obj;
		if (name == null) {
			if (other.name != null)
				return false;
		} else if (!name.equals(other.name))
			return false;
		return true;
	}
}

class Employee extends Person{
	private Company company;
	private double salary;
	public Employee(String name, int avg, boolean gender, String str, Company company, double salary) {
	    super(name, avg, gender, str);
		this.company = company;
		this.salary = salary;
	}
	@Override
	public String toString() {
		return super.toString()+"-"+company.toString()+"-"+salary;
	}
	@Override
	public boolean equals(Object obj) {
		if(super.equals(obj)==true) {
			Employee other = (Employee)obj;
			if(this.company.toString()==null||other.company.toString()==null) {
				return false;
			}
			String df1 = new DecimalFormat("#.#").format(this.salary);
			String df2 = new DecimalFormat("#.#").format(other.salary);
			if(this.company.toString().compareTo(other.company.toString())==0&&df1.compareTo(df2)==0) {
				return true;
			}
		}
		return false;
	}
	public Company getCompany() {
		return company;
	}
	public double getSalary() {
		return salary;
	}
	
}
public class Main {
	public static void main(String[] args) {
		// TODO Auto-generated method stub
		Scanner sc = new Scanner(System.in);
		String c;
		String nameString;
		int avg;
		boolean gender;
		ArrayList<Person> persons = new ArrayList<Person>();
		ArrayList<Student> students = new ArrayList<Student>();
		ArrayList<Employee> employees = new ArrayList<Employee>();
		String tempString;
		String stuNoString;
		String company;
		String clazzString;
		double salary;
		while(true) {
			c = sc.next();
			if(c.compareTo("s")==0) {
				nameString = sc.next();
				avg = sc.nextInt();
				gender = sc.nextBoolean();
				stuNoString = sc.next();
				clazzString = sc.next();
				Student tempStudent = new Student(nameString, avg, gender, c, stuNoString, clazzString);
				persons.add(tempStudent);
			}else if(c.compareTo("e")==0) {
				nameString = sc.next();
				avg = sc.nextInt();
				gender = sc.nextBoolean();
				salary = sc.nextDouble();
				company = sc.next();
				Company company2 = new Company(company);
				Employee tempEmployee = new Employee(nameString, avg, gender, c, company2, salary);
				persons.add(tempEmployee);
			}else {
				persons.sort(Comparator.comparing(Person::getName).thenComparingInt(Person::getAvg));
				for(int i=0;i<persons.size();i++) {
					if(persons.get(i).getStr().compareTo("s")==0) {
						System.out.println("Student:"+persons.get(i).toString());
						int flag = 0;
						for(int j=0;j<students.size();j++) {
							if(students.get(j).equals(persons.get(i))) {
								flag=1;
								break;
							}
						}
						if(flag == 0) {
							students.add((Student) persons.get(i));
						}
						
					}else {
						System.out.println("Employee:"+persons.get(i).toString());
						int flag = 0;
						for(int j=0;j<employees.size();j++) {
							if(employees.get(j).equals(persons.get(i))) {
								flag = 1;
								break;
							}
						}
						if(flag == 0) {
							employees.add((Employee)persons.get(i));
						}
						
					}
				}
				tempString = sc.next();
				if(tempString.compareTo("exit")==0||tempString.compareTo("return")==0) {
					return;
				}
				System.out.println("stuList");
				for(int i=0;i<students.size();i++) {
					System.out.println("Student:"+students.get(i).toString());
				}
				System.out.println("empList");
				for(int i=0;i<employees.size();i++) {
					System.out.println("Employee:"+employees.get(i).toString());
				}
				
			}
		}
	}
}